7. Expand and simplify the following: A. 7(3n - 9n + 8) - 8(-3 - 10n + 4n)
B. (n - 9) (n - 8) + 3(4n = 5)

i dont know

step-by-step explanation:

step-by-step explanation:

the original amount doesn't ''re just looking for the time it takes for 1/2 of the substance to we have

(1/2) =)     take the ln   of both sides

ln (1/2)   = )   and we can write

ln(1/2) = ) lne     and lne   = 1     so we have

ln(1/2) = -.1092t     divide both sides by -.1092

t = ln(1/2)/-.1092 = about 6.347 days = about 6.3 days (rounded)

answer: it is d

step-by-step explanation: