A new highway is to be constructed. Design A calls for a concrete pavement costing ​$70 per foot with a 20​-year ​life;

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A new highway is to be constructed. Design A calls for a
concrete pavement costing ​$70 per foot with a 20​-year ​life; four
paved ditches costing ​$5 per foot​ each; and our box culverts
every​ mile, each costing ​$7,000 and having a 20​-year life.
Annual maintenance will cost ​$1,900 per​ mile; the culverts
must be cleaned every five years at a cost of ​$400 each per mile.
Design B calls for a bituminous pavement costing ​$55 per foot with
a 10​-year life; two sodded ditches costing ​$1.55 per
foot​ each; and four pipe culverts every​ mile, each
costing ​$2,100 and having a 10​-year life. The replacement
culverts will cost $2,350 each. Annual maintenance will cost
​$2,800 per​ mile; the culverts must be cleaned yearly at a
cost of ​$225 each per​ mile; and the annual ditch maintenance
will cost ​$1.30 per foot per ditch. Compare the two designs on the
basis of equivalent worth per mile for a 20​-year period. Find the
most economical design on the basis of AW and PW if the MARR is
10​% per year
The AW value for Design A is
The PW value for Design A is
The AW value for Design B is
The PW value for Design B is