Solve for a (please type ONLY the numerical value): a+ 3.5 = 3.7 PLEASE BE FAST! THIS IS Q UIZ I WILL GIVE CREDIT!

Aroulette wheel has 38 slots in which the ball can land. two of the slots are green, 18 are red, and 18 are black. the ball is equally likely to land in any slot. the roulette wheel is going to be spun twice, and the outcomes of the two spins are independent.the probability that it lands one time on red and another time on black in any order is(a) 0.5 (b) 0.25 (c) 0.4488 (d) 0.2244

Atown has a population of 17000 and grows at 2.5% every year. to the nearest year, how long will it be until the population will reach 19600?

Mr vale buys 48 flowers. he puts bunches of 6 flowers each in vases. if he sells each vase for $2, how much dose he earn?