The ratio of Liam's age to his brother's age is 4:9. Liam is 10 years younger than his brother. How old is Liam now?

Iam so stuck. what is the worked out answer for this question?

If 10 men take 18 days to mow 60 acres of grass, how long will 15 men take to mow 80 acres?

In the following diagram it is given that dec,ab || dc, ad || eb, and ad is congruent to bc. a)why isn't abc a parallelogram even though it has a pair of parallel sides and a pair of congruent sides b)explain why be must be congruent to bc. further explain what type of triangle this makes triangle abc and what it tells you about angle 1 and angle 2c) finally why must angle 3 be congruent to angle 1? further, explain why we know that angle 3 is congruent to angle 2