Which of the following is true concerning an independent, three dimensional system

1. what is the measure of ∠abc? what is the measure of ∠abd?

Aparking garage charges $1.12 for the first hour and 0.50 for each additional hour. what is the maximum length of time tom can park in the garage if we wishes to play no more than $5.62

When you flip a biased coin the probability of getting a tail is 0.6. how many times would you expect to get tails if you flip the coin 320 times?