An isotope of the element erbium has a half-lifeof approximately 12 hours. Initially there are 49.1 grams of theisotope present. What is the rate of decay at t = 15.4 hours?

a.-13.9825 grams/hour

b. 13.9825 grams/hour

c.1.6810 grams/hour

d. 1.1652 grams/hour

e.-1.6810 grams/hour

f.-1.1652 grams/hour

2. What is the tangent line to

y=x4.8x when x = 4.3?

a.y = 0.8339x + 2019420.7357

b.y = 8083554.0594x + -32739878.9323

c.y = 4.0029x + 2019403.5230

d.y = -4.0029x - 2019420.7357

e.y = 4.0029x + 17.2126

f.This tangent line does not exist