Given :
Measurements
.
To Find :
The multiplication using significant figures .
Solution :
We know , the least number of significant figures in any number of the problem determines the number of significant figures in the answer.
So , significant figure( S.F) in 4.5 cm is 2 .
S.F in 2000.0 cm is 5 .
S.F in 4 cm is 1 .
So , minimum S.F is 1 .
Therefore , S.F of their product is 1 .
Now , multiplying them we will get :

Now , converting 36000 in 1 significant digit .
First we will write it in exponential 2 S.F form.

Now , to convert 3.6 into 1 S.F we should round off this .
So , round off 3.6 we will get 4 .
Therefore , The multiplication using significant figures is
.
Hence , this is the required solution .
Answer:
Yeah its true.................
Explanation:
True
Answer:
No reaction.
Explanation:
An Arrhenius base (like NaOH) increases the concentration of hydroxide ions present in the solution.
If you add Rb to an aqueous solution of NaOH, you will get an explosion.
However, the Rb does not react with the OH^-. Instead, it reacts rapidly with the water.
2Rb + 2H2O → 2RbOH + H2
So much heat is generated that the hydrogen explodes:
2H2 + O2 → 2H2O