Answer:
∠72°.
Step-by-step explanation:
If a circle has a circumference of 20 and an arc with a length of 4, we can simply set up a ratio to determine the angle of the arc in degrees:

Cross multiply:

Divide both sides by '20':
x = 72°.
Therefore, the measure of the central angle of the arc is ∠72°.
Franny: 2.849 tons is the answer
Answer:
Gerri spends 1/7 (A).
Step-by-step explanation:
If Gerri spends 1/21 of her money on pencils and 2/21 of her money on paper, adding these two fractions together will give us the total fraction of her money that she spent. Since 1/21 and 2/21 have the same denominator, we can add the numerators to get 3/21. However, fractions must always be in simplest form, meaning if the numerator (top number) and denominator (bottom number) can both be divided evenly by the same factor, then the fraction can be simplied to lower numbers. In this case the number 3 and the number 21 can both be divided evenly by 3: (3÷3)/21÷3) = 1/7.
Max height is the vertex
convert to vertex form (y=a(x-h)^2+k) by completeing the square
h(t)=-16(t²-4t)+80
h(t)=-16(t²-4t+4-4)+80
h(t)=-16((t-2)²-4)+80
h(t)=-16(t-2)²+64+80
h(t)=-16(t-2)²+144
vertex is (2,144)
at t=2, the height is 144
max height is 144ft