Code:#include <stdio.h>double washerWeight(double,double,double);//prototype double circleArea(double,double);//prototype //void printWeights int main(void) { double quant,thick,dens,innerd,outerd,circleA1,weight1; printf("Enter quantity,thickness,density,inner diameter,outer diameter of Washer Type A"); scanf ("%lf %lf %lf %lf %lf", &quant,&thick,&dens,&innerd,&outerd); circleA1 = circleArea(innerd,outerd); weight1 = washerWeight(quant,thick,dens); //printf("%lf",a); return 0; } double washerWeight(double x,double y, double z); { return x*y*z; } double circleArea(double inner,double outer); { double pi = 3.142; outerArea = pi*outer*outer/4; innerArea = pi*inner*inner/4; totalArea = outerArea - innerArea; return(totalArea); } /*void printWeights(double) { } Derp.c:37: error: expected identifier or '(' before '{' token Derp.c:42: error: expected identifier or '(' before '{' token those errors */