Answer:

Step-by-step explanation:
we are given half-life of PO-210 and the initial mass
we want to figure out the remaining mass <u>after</u><u> </u><u>4</u><u>2</u><u>0</u><u> </u><u>days</u><u> </u>
in order to solve so we can consider the half-life formula given by

where:
- f(t) is the remaining quantity of a substance after time t has elapsed.
- a is the initial quantity of this substance.
- T is the half-life
since it halves every 140 days our T is 140 and t is 420. as the initial mass of the sample is 5 our a is 5
thus substitute:

reduce fraction:

By using calculator we acquire:

hence, the remaining sample after 420 days is 0.625 kg
4:1,
there are 4 cups of water for every 1 cup of sugar
Answer:
The car was travelling at a speed of 60 miles per hour.
Step-by-step explanation:
Given:
Distance traveled = 330 miles
Time Period = 
we need to find the speed of the car .
Solution:
Time Period = 
Now we can say that;

So Time period = 
Now we know that;
Distance traveled
is equal to Speed
multiplied by Time Period
.
framing in equation form we get;

Dividing both side by 5.5 we get;

Hence The car was travelling at a speed of 60 miles per hour.
The dashed line is because the sign is greater than to be a solid line it has to be equal to or greater than and to the shading means any point on there works for the equation easiest way to test where you should shade is by plugging into the equation the point (0,0)
Mulitpilicty is how many times a root repeats
factor
factor x first
x(2x^2+x-1)
using math
(x)(x+1)(2x-1)
no roots repeat
if it is equal to 0 then the roots are
0 multiplicty 1
-1 multiplicty 1
1/2 multiplicty 1