Answer:
option A= Physical change
Explanation:
physical change:
" It is a change in which no new substance is formed"
Breaking of object like glass is the example of physical change because it is not change into another object. It effect the form of object but can not change the chemical composition.
Chemical changes:
" it is a change in which one substance is converted into new product through chemical reaction".
During the chemical changes the types and the number of atom remain same but their arrangement changed.
for example: burning of wood, baking of cake, digesting food, resting of iron etc.
Physical reaction:
" physical reaction occur during the molecular rearrangement. There is no chemical change occur"
In this type of changes no bonds are break to form new bonds, for example boiling point.
Chemical reaction:
" chemical reaction occur when molecules are chemically react with each others and bonds formation and breaking is also occur"
Don’t click that link EVER, they try to use your camera fsr
Answer:
can you send me a picture of what layer a and look b look like and then I will be able to evaluate
Sodium bicarbonate is commonly known as baking soda. The scientific name is NaHCO3. Baking soda is an alkaline compound found in crystalline form in nature.
Hope this helped
Brainliest is appreciated
Good luck
~ Emmy
Answer:
Cost to supply enough vanillin is 
Explanation:
Threshold limit of vanillin in air is
per litre means there should be
of vanillin in 1L of air to detect aroma of vanillin.

So, 
So amount of vanillin should be present to detect = 
As cost of 50 g vanillin is
therefore cost of
vanillin = 