If 4 are $2.00 , then x3 to get 12 light bulbs and 2x3=6 so it's $6.00
Answer:
a)
, b)
, c)
, d) 
Step-by-step explanation:
a) Let assume an initial mass m decaying at a constant rate k throughout time, the differential equation is:

b) The general solution is found after separating variables and integrating each sides:

Where
is the time constant and 
c) The time constant is:


The particular solution of the differential equation is:

d) The amount of radium after 300 years is:

I think the answer is d or b if im wrong sorry hope this helped tho :p
Answer:
yes i agree with you!!!
Step-by-step explanation: