Answer:
a) What is the surface temperature, in °C, after 400 s?
T (0,400 sec) = 800°C
b) Yes, the surface temperature is greater than the ignition temperature of oak (400°C) after 400 s
c) What is the temperature, in °C, 1 mm from the surface after 400 s?
T (1 mm, 400 sec) = 798.35°C
Explanation:
oak initial Temperature = 25°C = 298 K
oak exposed to gas of temp = 800°C = 1073 K
h = 20 W/m².K
From the book, Oak properties are e=545kg/m³ k=0.19w/m.k Cp=2385J/kg.k
Assume: Volume = 1 m³, and from energy balance the heat transfer is an unsteady state.
From energy balance: 
Initial temperature wall = 
Surface temperature = T
Gas exposed temperature = 
I think because if you’ve already turned it in they might as well grade asap instead of waiting
Answer:
Codes for each of the problems are explained below
Explanation:
PROBLEM 1 IN C++:
#include<iostream>
using namespace std;
//fib function that calculate nth integer of the fibonacci sequence.
void fib(int n){
// l and r inital fibonacci values for n=1 and n=2;
int l=1,r=1,c;
//if n==1 or n==2 then print 1.
if(n==1 || n==2){
cout << 1;
return;
}
//for loop runs n-2 times and calculates nth integer of fibonacci sequence.
for(int i=0;i<n-2;i++){
c=l+r;
l=r;
r=c;
cout << "(" << i << "," << c << ") ";
}
//prints nth integer of the fibonacci sequence stored in c.
cout << "\n" << c;
}
int main(){
int n; //declared variable n
cin >> n; //inputs n to find nth integer of the fibonacci sequence.
fib(n);//calls function fib to calculate and print fibonacci number.
}
PROBLEM 2 IN PYTHON:
def fib(n):
print("fib({})".format(n), end=' ')
if n <= 1:
return n
else:
return fib(n - 1) + fib(n - 2)
if __name__ == '__main__':
n = int(input())
result = fib(n)
print()
print(result)
Answer:
gauge pressure is 133 kPa
Explanation:
given data
initial temperature T1 = 27°C = 300 K
gauge pressure = 300 kPa = 300 × 10³ Pa
atmospheric pressure = 1 atm
final temperature T2 = 77°C = 350 K
to find out
final pressure
solution
we know that gauge pressure is = absolute pressure - atmospheric pressure so
P (gauge ) = 300 × 10³ Pa - 1 × 
Pa
P (gauge ) = 2 × Pa
so from idea gas equation
................1
so 
P2 = 2.33 × Pa
so gauge pressure = absolute pressure - atmospheric pressure
gauge pressure = 2.33 × - 1.0 ×
gauge pressure = 1.33 × Pa
so gauge pressure is 133 kPa
