What 3 things is the respiratory system made up of?

Why is it important that salads have crunch factors, color, and appropriate dressings? a. the salad will appeal to customers with varied tastes. b. it is easy to get away with poor quality ingredients. c. it is a good way to use up leftovers. d. it will give the customer something to enjoy in each bite. e. it use more products.

Astairway has 6 steps. is it a handrail required? a. a handrail is required b. a handrail is not required c. double handrails are required d. only nosing is required

Which of the following could use reverse transcriptase to transcribe its genome? a) ssrnab) dsrnac) ssdnad) dsdna