Part a .
A arithmetic sequence with a third term of 8 and a common difference of 5 .
To find the first five therms, since the common difference is 5, so we add 5 to get the fourth term and add 5 to fourth term to get the fifth term .
And for first two terms, we will subtract 5 from 8 to get the second term and subtract 5 from the second term to get the first term. And we will get

Part b:A geometric sequence with a fifth term of 1/3 and constant ratio of 1/3.
TO find the first five terms, since the constant ratio of 1/3, so we multiply 1/3 to third term to get fourth term, and multiply fourth term by 1/3 to get fifth term .
And to get the first two terms, we will divide third term by 1/3, to get the second term and divide the second term by 1/3 to get the first term, that is

Basing on the description, a parabola opening up with vertex at origin, the formula with vertex at origin is used, x^2 = 4py. p is the focus and so with the dimensions given, we obtain a 0.25 and that is the distance of the focus to the vertex.
Answer:
y=4-5/3x
Step-by-step explanation:
Rearrange and simplify.
(7 3/4 mi/h)*(2 2/3 h) = 20 2/3
Todd rode 20.667 miles.
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A calculator that works with mixed numbers is a handy thing.