One positive number is 4 more that twice another. is the product

Ahigh-altitude spherical weather balloon expands as it rises, due to the drop in atmospheric pressure. suppose that the radius r increases at the rate of 0.02 inches per second, and that r = 36 inches at time t = 0. determine the equation that models the volume v of the balloon at time t, and find the volume when t = 360 seconds. v(t) = 4π(0.02t)2; 651.44 in3 v(t) = 4π(36 + 0.02t)2; 1,694,397.14 in3 v(t) = four pi times the product of zero point zero two and t to the third power divided by three.; 4,690.37 in3 v(t) = four pi times the quantity of thirty six plus zero point zero two t to the third power divided by three.; 337,706.83 in3

X= 3y - 6 2x - 4y = 8 solve the system of equations using substitution. a) (-12,-2) b) (15,7) c) (21,9) d) (24,10)

Ashipment of 18 cars, some weighing 3000lb a piece and th eothers 5000lb each, has a total weight of 30 tons. find the number of each kind of car.