An electric kettle has a power rating of 2.4kW. How long does it take the kettle to heat up 4.5kg of tap water from 28°C to 100°C ? (c of water = 4200Jkg1°C-) What assumption must you make to arrive the answer ? pls helppp

find the surface area of the sphere to the nearest square unit. use a calculator.

a. 254 in.2

b. 64 in.2

c. 127 in.2

d. 1,018 in.2

it is given that trillions of microbes make up to 1% to 3% of the body mass.

let's take average of this percentage: 2%

consider the average mass of the human body as 70 kg.

then, trillions of microbes would have mass  

therefore, 100 trillion micro-organisms would weigh:

this is an approximate value and could change depending on the mass of the human body and percentage of the microbes present in it.

average mass per microorganism =