1.

assume cs:codedata segment db 'welcome to masm! ',0data endscode segmentstart:    mov ax,cs    mov ds,ax    mov si,offset capital    mov ax,0    mov es,ax    mov di,200h    mov cx,offset capitalend-offset capital    cld    rep movsb    mov ax,0    mov es,ax    mov word ptr es:[7ch*4],200h    mov word ptr es:[7ch*4+2],0    mov dh,10    mov dl,    10    mov cl,2    mov ax,data    mov ds,ax    mov si,0    int 7ch        mov ax,4c00h    int 21hcapital:    push ax    push es    push di    push si    mov ax,0b800h    mov es,ax    mov al,0a0h    mul dh    mov di,ax    mov al,2    mul dl    add di,ax    mov ah,cls:    mov al,[si]    cmp al,0    je ok    mov word ptr es:[di],ax    add di,2    inc si    jmp short sok:    pop si    pop di    pop es    pop ax    iretcapitalend:    nopcode endsend start

 2.

assume cs:codecode segmentstart:    mov ax,cs    mov ds,ax    mov si,offset capital    mov ax,0    mov es,ax    mov di,200h    mov cx,offset capitalend-offset capital    cld    rep movsb    mov ax,0    mov es,ax    mov word ptr es:[7ch*4],200h    mov word ptr es:[7ch*4+2],0    mov ax,0b800h    mov es,ax    mov di,12*160    mov bx,offset s-offset se    mov cx,80s:    mov byte ptr es:[di],'!'    add di,2    int 7chse:    nop    mov ax,4c00h    int 21hcapital:    push bp    mov bp,sp    dec cx    jcxz ok    add [bp+2],bxok:    pop bp    iretcapitalend:    nopcode endsend start