Question

wrong answers your all answers are wrong
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Answer 1

Step-by-step explanation:

Melting a sugar cube is a physical change because the substance is still sugar. Burning a sugar cube is a chemical change. Fire activates a chemical reaction between sugar and oxygen. The oxygen in the air reacts with the sugar and the chemical bonds are broken.

Answer 2

Answer:

Using LCM method you can solve this question in the following manner-

GIVEN :-

A & B together takes 6 days and A alone takes 15 days to complete the work

we can write it as -

A+B = 6

A= 15

Now finding total unit work by taking LCM of 6 & 15 which is 30

Total unit work = 30

Now finding unit work completed in 1 day by dividing total unit work by their respective 1 day work

Unit work done in 1 day-

A+B=30/6=5 ——-(1)

A=30/15=2 ——-(2)

Putting value of A in eq. (1) we get

B=3

Now for finding total days required by them to complete the whole work alone we will divide the total unit work their respective 1 day work-

Hence total days required by B to complete the whole work alone is-

30/3=10 days