3rd grade math!

which of the following are characteristics that a rectangle must have?

i. opposite sides have the same length
ii. all sides have the same length
iii. all angles have different sizes
iv. all angles are the same size

Which of these numbers of simulations of an event would be most likely to produce results that are closest to those predicted by probability theory? 15, 20, 5, 10

At a local museum, the total price for one adult and one child is $11. mrs. smith paid for herself and her three children. she spent $19. record the system of equations to be solved and then find the price of an adult and child ticket using either elimination or substitution.

When steve woke up. his temperature was 102 degrees f. two hours later it was 3 degrees lower. what was his temperature then?