A chemical has a half-life of 10 days. If you started with 250 mg of the substance, how long will it take for it to reach 100 mg? PLEASE HELP!!!

The function a represents the cost of manufacturing product a, in hundreds of dollars, and the function b represents the cost of manufacturing product b, in hundreds of dollars. a(t) = 5t + 2 b(t) = 7t - 2t +4 find the expression that describes the total cost of manufacturing both products, a(t) + b(t). a. 7t^2 - 7t + 2 b. 7t^2 + 3 +6 c. 7t^2 + 7t - 6 d. 7t^2 - 3t + 6

How long must $542 be invested at a rate of 7% to earn $303.52 in interest? in a easier way

Find the value of x. give reasons to justify your solutions! h ∈ ig