Line u passes through points (10, 8) and (6, 11). Line v passes through points (2, 2) and (5, 6). Are line u and line v parallel or perpendicular?

I’m stuck on this equation, anyone got the answer?

Susie wants to take her friend out for lunch.she wants to spend $9.75 each person. how much will she spend in all.

The half-life of a certain material is 0.004 second. approximately how much of a 20-gram sample will be left after 0.016 second? a. 5 grams b. 16 grams c. 0.32 gram d. 1.25 grams