function hid()
{
ab.style.visibility="hidden"
bpo.style.visibility="hidden"
com.style.visibility="hidden"
sar.style.visibility="hidden"
}

function ww1()
{
ab.style.visibility="visible"
bpo.style.visibility="hidden"
com.style.visibility="hidden"
sar.style.visibility="hidden"
}

function ww2()
{
ab.style.visibility="hidden"
bpo.style.visibility="visible"
com.style.visibility="hidden"
sar.style.visibility="hidden"
}
function ww3()
{
ab.style.visibility="hidden"
com.style.visibility="visible"
bpo.style.visibility="hidden"
sar.style.visibility="hidden"
}
function ww4()
{
ab.style.visibility="hidden"
sar.style.visibility="visible"
com.style.visibility="hidden"
bpo.style.visibility="hidden"
}