Answer:
![\boxed{\sf Time \ being \ in \ which \ body \ remains \ in \ air = 4 \ s}](https://img.qammunity.org/2021/formulas/physics/high-school/lppieivy1j2lzds7llpozuy16q9fnyqkbj.png)
Given:
Velocity (u) = 20 m/s
Acceleration due to gravity (g) = 10
![\sf m/s^2](https://img.qammunity.org/2021/formulas/physics/high-school/l459edggj7phasmkavmcfwwli2y9dy44qo.png)
To Find:
Time (t) being in which body remains in air.
Step-by-step explanation:
Formula:
![\boxed{\bold{\sf t=(2u)/(g)}}](https://img.qammunity.org/2021/formulas/physics/high-school/43kirer179py9yr69klnohga90dtj0new5.png)
Substituting values of u & g in the equation:
![\sf \implies t = (2 * 20)/(10)](https://img.qammunity.org/2021/formulas/physics/high-school/xo3n6qbmobqdvgf6l052eb7ao02rqlq4nz.png)
![\sf \implies t =(40)/(10)](https://img.qammunity.org/2021/formulas/physics/high-school/3sgk9mzz056vka5kd92ztibt238lm4hhuo.png)
![\sf \implies t =\frac{4 * \cancel{10}}{ \cancel{10}}](https://img.qammunity.org/2021/formulas/physics/high-school/tga7ee1bynqngazceqa7ebxe317vo5yeov.png)
![\sf \implies t = 4 \ s](https://img.qammunity.org/2021/formulas/physics/high-school/xbue2si7off4zttnzl552r9jsm7qdcr1z3.png)
![\therefore](https://img.qammunity.org/2021/formulas/mathematics/high-school/zvcp35s3bq26ivrtwrqv1wpy3rbhge44qb.png)
Time (t) being in which body remains in air = 4 seconds