(d) Veins have different structures from arteries. State two features of veins and explain how these features enable them to function efficiently.

1. Featu

Explanation

2. Featu

Explanation​

here's the solution,

Feature 1 : -

veins have thin walls as compared to arteries.

Explaination 1 : -

veins have thin walls, because they have less blood pressure in comparison to arteries and hence.

Feature 2 : -

veins have valves

Explanation 2 : -

veins have valves to stop backflow of blood.

burning of wood and coal

explanation:

the panel also concluded there's a better than 95 percent probability that human-produced greenhouse gases such as carbon dioxide, methane and nitrous oxide have caused much of the observed increase in earth's temperatures over the past 50 years.

coconut why: has water in it : )