Hi, I've been trying to get this program to work for class. I have been having trouble with functions and decided to make the program more simple, but I am still getting errors. Any help would be appreciated.

This is my program:

Code:
#include<stdio.h>
void readdata (float*, float*, float*, float*, float*);
float area (float, float);
float weight (float, float, float, float);
void printresult (float);

float main(void)
{
float q1, t1, d1, id1, od1, ida1, oda1, rim1, w1;
readdata(&q1, &t1, &d1, &id1, &od1);
rim1=area(id1, od1);
w1=weight(q1, t1, d1, rim1);
printresult(w1);
return 0;
}

void readdata (float *q1, float *t1, float *d1, float *id1, float *od1)
{

printf("Enter the Quantity, Thickness, Density, Inner Diameter, and Outer 
Diameter for Washer A:\n");
scanf("%f %f %f %f %f", &q1, &t1, &d1, &id1, &od1);
}


float area (float id1, float od1);
{
float ida1, oda1, rim1;
ida1= ((id1/2)*(id1/2))*3.142
oda1= ((od1/2)*(od1/2))*3.142
rim1= oda1-ida1
}


float weight (float q1, float t1, float d1, float rim1)
{
w1= q1*t1*d1*rim1
}

void printresult (float w1);
{
printf("The weight of Washer A is: %f\n", w1);
}

These are the errors I am getting:

"benice.c", line 20: newline in string literal
"benice.c", line 21: syntax error before or at: Diameter
"benice.c", line 21: invalid source character: '\'
"benice.c", line 21: newline in string literal
"benice.c", line 28: syntax error before or at: float
"benice.c", line 37: undefined symbol: w1
"benice.c", line 38: syntax error before or at: }
"benice.c", line 42: syntax error before or at: printf
cc: acomp failed for benice.c

Again, any help is appreciated. Thanks a lot.