Felicity Smoak first appears in the third episode of the first season of the series Arrow. She is introduced as an IT expert working at Queen Consolidated, where she assists Oliver Queen with his mission as the vigilante Arrow. Felicity quickly becomes a key member of Team Arrow and plays a significant role throughout the series. **

Oliver and Felicity officially get together in the 20th episode of the third season of Arrow, titled "The Fallen." This episode marks a significant moment in their relationship as they finally admit their feelings for each other and share a passionate kiss. Their romantic relationship continues to evolve throughout the series, with its ups and downs. **

The valves on heating pipes are typically ball valves or gate valves. Ball valves have a spherical disc inside that controls the flow of water by rotating the handle, while gate valves have a gate or wedge that moves up and down to control the flow. Both types of valves are used to regulate the flow of hot water through the heating system and can be manually operated to adjust the temperature or shut off the flow completely. **

The episode where Felicity spies on Oliver and finds his secret prison on an island is in Season 5, Episode 17 titled "Kapiushon." In this episode, Felicity discovers Oliver's secret prison on the island of Lian Yu, which he used to keep his enemies captive. This discovery leads to a confrontation between Felicity and Oliver, as she is shocked and disappointed by his actions. The episode delves into Oliver's dark past and the morally questionable decisions he has made in his quest to protect Star City. **

The episode you are referring to is from Season 1, Episode 21 titled "The Undertaking." In this episode, Felicity hacks into Oliver's computer and discovers the location of his private prison on the island of Lian Yu. This discovery leads to a significant turning point in their relationship and sets the stage for future storylines in the series. **

Yes, the consumption of energy-saving pumps may increase when replacing heating pipes. This is because energy-saving pumps are designed to operate more efficiently and effectively with newer heating systems and pipes. The improved performance of the energy-saving pumps may lead to increased usage, as they are able to distribute heat more evenly and effectively throughout the system. Additionally, the replacement of old pipes with newer, more efficient ones may also contribute to increased energy consumption, as the system may be able to operate more efficiently overall. **

Some recommended mixers for cocktails include soda water, tonic water, ginger beer, and fruit juices such as orange, cranberry, and pineapple. These mixers can be used to create a wide variety of classic and modern cocktails, and can be easily combined with various spirits to create refreshing and flavorful drinks. Additionally, simple syrup and bitters are also commonly used as mixers to add sweetness and depth of flavor to cocktails. **

Suspension filtration works by passing a mixture of solid particles and liquid through a filter medium. The solid particles are too large to pass through the filter, so they are retained on the surface or within the pores of the filter. The liquid, which is now free of the solid particles, passes through the filter and is collected on the other side. This process separates the solid particles from the liquid, allowing for the purification or concentration of the liquid. **