There are several information's already given in the question. Based on the information's provided, the answer can be easily deduced.
V1 = 25 ml
= 25/1000 liter
= 0.025 liter
V2 = 18 ml
= 18/1000 liter
= 0.018 liter
M2 = 1.0 M
M1 = ?
Then
M1V1 = M2V2
M1 = M2V2/V1
= (1 * 0.018)/0.025
= 0.72 M
From the above deduction, it can be easily concluded that the correct option among all the options that are given in the question is the first option or option "A". I hope that this is the answer that has actually come to your help.
1st qn - B
2nd qn - A
Last qn - Yes
Answer: The geologic time scale is the “calendar” for events in Earth history. It subdivides all time into named units of abstract time called—in descending order of duration—eons, eras, periods, epochs, and ages.
Explanation: I learned about it the other day
Standard Temperature and Pressure (STP) are 273.15 K (Kelvin) and 101.3 KPa (kilopascals).
You can substitute 1 ATM (atmosphere) for the kilopascal measurement. It is discouraged to use 0°C for the temp equivalent since negative temperature numbers can't be used in gas equations..