Answer:
I think the answer is c because the arrow has to pointing positive.
Okay the scale for this equation is each inch equals 30 miles. SO to get how many miles 4.5 inches equals to, we have to multiply 30 by 4.5, and the answer we get is 135.
I hope this helps!
D because y (time spent) = 50 × x (distance travelled)
225÷4.5=50
x÷y=50
Say the width is W and the length is L
L=3W (and of course W=W)
Now you use the perimeter formula P=2L+2W
80=2(3W) + 2W)
80=6W+2W
80=8W Divide both sides by 8
W=10
Now that you know the width, substitute it back into L=3W to find the length
L=3(10)
L=30
The dimensions are length: 30 cm and width: 10 cm
The half life of the substance is 6.92 days.
<h3>What is the Half life ?</h3>
Half life can be defined as the time required to reduce the concentration to half of its initial value.
Here the equation given is
The concentration will reduce to half therefore
so,
ln 0.5 = - 0.1001 * t(1/2)
-0.693 = -.1001 * t(1/2)
t(1/2) = 6.92 days.
Therefore the half life of the substance is 6.92 days.
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