#pragma GCC optimize("Ofast")
#pragma GCC target("avx2")

#define rd_init() char*rp=({char*mmap();mmap(0l,1l<<25,1,2,0,0ll);})
#define rd() ({int _v=0,_c;while(_c=*rp++-48,_c>=0)_v=_v*10+_c;_v;})
#define wt(v) ({unsigned _z=v;do*--wp=_z%10+48;while(_z/=10);})
#define wt1(v) ({char wbuf[64],*wp=wbuf+sizeof wbuf;wt(v);write(1,wp,wbuf+sizeof wbuf-wp);})
#define rep(v,e) for(typeof(e) v=0;v<e;++v)
#define MD 1000000007

typedef unsigned long ulong;

void sort_aux(unsigned*a,unsigned*b,int n){
	int c[256];
	for(int i=0;i<256;++i){
		c[i]=0;
	}
	for(int i=0;i<n;++i){
		++c[a[i]&255];
	}
	int t=0;
	for(int i=256;i--;){
		int u=c[i];
		c[i]=t;
		t+=u;
	}
	for(int i=0;i<n;++i){
		b[c[a[i]&255]++]=a[i]>>8|a[i]<<24;
	}
}

void sort(unsigned*a,int n){
	static unsigned b[100000];
	sort_aux(a,b,n);
	sort_aux(b,a,n);
	sort_aux(a,b,n);
	sort_aux(b,a,n);
}

unsigned v[100000];

ulong fac(ulong n){
	static unsigned const fac8[]={
		        1, 988636580, 695283030, 792464830, 211210084, 690746858, 350191551, 426484032,  41710039, 813460239,
		558164830, 141497103, 950738028, 464835272,  97894695, 916372711, 110247743, 969786090, 503068962, 429662713,
		960011178,  28831697,  64164502, 644858472, 580681420, 685687553, 732369763, 284072362, 973536426, 691577297,
		138616501, 791335653, 857536770, 418934534,  59993985, 649008795, 469845601, 262024866,  82355309, 762601625,
		779906992, 700811164, 768370249, 627482638, 120082832, 889761575, 393698932, 315006352, 501868614, 389081755,
		110949981,  73117756, 246998080, 810960304, 899599758,  54240893, 285492803, 238086226, 756915097, 857420303,
		590237245, 189189356,  27740096, 365659876, 182153956,  74775714, 449611889, 604699923, 708964844,  29899448,
		434888300, 577073314, 913463884, 898026807, 117764246, 666808812, 948824387, 773943041, 562701063, 968037475,
		324433771, 116780897, 718140143, 843054228, 916823404, 472625466, 934718736, 369384614, 632057771, 319626719,
		855456001, 487389069, 688736405, 168349895, 918820931, 450077038, 715100901,  12311664, 
	};
	ulong z=fac8[n>>10];
	for(;n&1023;--n){
		z=z*n%MD;
	}
	return z;
}

ulong modpow(ulong a,ulong b){
	ulong r=1;
	while(b){
		if(b&1){
			r=r*a%MD;
		}
		b>>=1;
		a=a*a%MD;
	}
	return r;
}

int inverse(int a){
	int b=MD;
	int u=1;
	int v=0;
	while(b){
		int q=a/b,t;
		t=b, b=a-q*b, a=t;
		t=v, v=u-q*v, u=t;
	}
	if(u<0){
		u+=MD;
	}
	return u;
}

int main(){
	rd_init();
	long n=rd();
	long m=rd();
	ulong p=(ulong)rd()*570000004%MD;
	ulong q=MD+1-p;
	p=modpow(p,m);
	ulong r=0;
	rep(i,n){
		unsigned vi=rd();
		v[i]=vi;
		r+=vi;
	}
	sort(v,n);
	ulong s=r;
	ulong t=0;
	ulong u=1;
	ulong c=fac(m-1);
	ulong k=1;
	ulong l=c;
	rep(i,n){
		t=(t*k+c*p%MD*u%MD*(s%MD))%MD;
		p=p*q%MD;
		u=u*k%MD;
		k=k*(i+1)%MD;
		c=c*(i+m)%MD;
		s-=v[i];
	}
	r=(r+MD-t*inverse(u*l%MD)%MD)%MD;
	wt1(r);
	_exit(0);
}