Answer:
Can you take picture, please?
Staals half
1 gram left
0.3 grams left
half lives are normally written in years
it goes likt this

A=final amount
P=initila amount
t=time elapsed
h=time half life is (same units as time)
let's use days as the units of time
we are given
initial amount=1gram
final amount=0.3gram
time=4 days
so

solve for h

take the ln of both sides


times both sides by h

divide both sides by ln(0.3)

use calculator
h=2.30287
3 sig figs
h=2.303 days
Answer:
16
Step-by-step explanation:
Area = perpendicular height * base
= DP * CB
= √[(2 - -1.2)^2 + (-5 - (-3.4)^ ] * √[(2 - 0)^2 + (3- -1)^2)]
= √(12.8.) * √(20)
= 16
=
Answer: 5
Step-by-step explanation: add 5 on each side and you get -50 then divide -5/2 with -50 and get 5