All of the following are characteristics of all living things except: 1.Reproduces
2.Needs nutrients
3.Has a heart
4Exchanges gas

hello from mrbilldoesmath!

answer:

a(n) - a(n-1) -3

discussion:

this ones a bit interesting. given a(n) = 5 - 3n consider this:

a(n-1) = 5 - 3(n-1)

          = (5 - 3n) + 3             => but a(n) = 5 - 3n, the first term

          = a(n)   + 3                 => subtract 3 from both sides

a(n-1) -3 = a(n)  

or

a(n) - a(n-1) -3

you,

mrb

step-by-step explanation:

b and c

51

step-by-step explanation:

73-22=51 the   mass number minus the amount of protons gives you the amount of neutrons

the answer is b.

64

step-by-step explanation:

c=2πr=2·π·8≈64