Answer:
The correct answer will be "0.756596 m²".
Explanation:
The given values are:
The radius of an umbrella,
r = 0.4 m
The height of an umbrella,
h = 0.45 m
As we know,
The lateral surface of an umbrella will be:
⇒
![\pi r√(r^2+h^2)](https://img.qammunity.org/2021/formulas/mathematics/high-school/pe05isyxa6z2lb23oncpwnrvk9fpddsvq4.png)
On substituting the values, we get
⇒
![\pi * 0.4√((0.4)^2=(0.45)^2)](https://img.qammunity.org/2021/formulas/mathematics/high-school/ku65f10bxfl9j849idqnkuqifrxe7hbns3.png)
⇒
![0.756596 \ m^2](https://img.qammunity.org/2021/formulas/mathematics/high-school/zsvi978pg2asqdim6jenxfyq0kemadcomq.png)
So that the amount of fabric needed will be "0.756596 m²".