Must be written in Python The amount of time students spent studying for an exam is exponentially distributed with a mean of 25 hours. Write a piece of code to compute the percentage of students who spent between 30 and 40 hours studying for the exam? Your code should print out the percentage rounded to 1 decimal place

Transient PopulationPopulations are affected by the birth and death rate, as well as the number of people who move in and out each year. The birth rate is the percentage increase of the population due to births and the death rate is the percentage decrease of the population due to deaths. Write a program that displays the size of a population for any number of years. The program should ask for the following data: The starting size of a population P The annual birth rate (as a percentage of the population expressed as a fraction in decimal form)B The annual death rate (as a percentage of the population expressed as a fraction in decimal form)D The average annual number of people who have arrived A The average annual number of people who have moved away M The number of years to display nYears Write a function that calculates the size of the population after a year. To calculate the new population after one year, this function should use the formulaN = P + BP - DP + A - Mwhere N is the…

n this lab, you complete a prewritten Python program for a carpenter who creates personalized house signs. The program is supposed to compute the price of any sign a customer orders, based on the following facts: The charge for all signs is a minimum of $35.00. The first five letters or numbers are included in the minimum charge; there is a $4 charge for each additional character. If the sign is make of oak, add $20.00. No charge is added for pine. Black or white characters are included in the minimum charge; there is an additional $15 charge for gold-leaf lettering.

plz explain python

I use python/pycharm when creating my answers.