By building its own shipping and delivery infrastructure, Amazon saves about $\_\_\_\_\_\_$ in third$-$party shipping costs, and $$click to door$$ delivery time was nearly $\_\_\_\_\_\_$ days better than the industry.

a$.$

$15\%$ in third party shipping costs and $4$ days better

b$.$

$33\%$ in third party shipping costs and $2$ days better

c$.$

$25\%$ in third party shipping costs and $3$ days better

d$.$

$25\%$ in third party shipping costs and $4$ days better

e$.$

$33\%$ in third party shipping costs and $3$ days bette