Answer
$H_{o}: μ = 4 hrs$ ,
$H_{1}: μ < 4 hrs$
Work Step by Step
Null hypothesis (a 4 hour drive without oil is possible with the product):
$H_{o}: μ = 4 hrs$,
Alternative hypothesis (one can drive less than 4 hours without oil with the product):
$H_{1}: μ < 4 hrs$
