bearing in mind that an explicit form is simply the sequence written as a function of some variables, so we simply simplify and add like-terms.
Answer:
ano ang pinag kaiba noon kaysa ngayon
In this question, there are 10 digit phone number which was divided into 3-3-4 digits. Every first digit of the division should be 2-9 which mean only 8 possibilities. The other digits would be 0-9 which mean 10 possibilities. Then the calculation would be:
8*10*10 * 8*10*10 * 8*10*10*10 = 8^3 * 10*7= 512 * 10^7= 5.12 * 10^9
If you convert <span>400,000,000 into the scientific form it will become 4* 10^8. Since 5.12*10^9 > 4 * 10^8, then it is clear that the number should be enough</span>
