Are the following if statements equivalent? If not, why not?

if $($score $90)$ if $($score $<mtext\; id="EditorElement\_92576"></mtext><mn\; id="EditorElement\_92577">6</mn><mn\; id="EditorElement\_92578">0</mn><mi\; id="EditorElement\_92579">)</mi>$

printf$("$A$")$; $,$ printf $("$F$")$;

else if $($score $>=80)$ else if $($score $<mtext\; id="EditorElement\_92535"></mtext><mn\; id="EditorElement\_92536">7</mn><mn\; id="EditorElement\_92537">0</mn><mi\; id="EditorElement\_92538">)</mi>$

printf$("$B$")$; $,$ printf$("$D$")$;

else if $($score $>=70)$ else if $($score $<mtext\; id="EditorElement\_92455"></mtext><mn\; id="EditorElement\_92456">8</mn><mn\; id="EditorElement\_92457">0</mn><mi\; id="EditorElement\_92458">)</mi>$

printf$("$C$")$; $,pr{\displaystyle \underset{\phantom{}}{\overset{\phantom{}}{}}}f(C)$;

else if $($score $>=60)$ else if $($score $<mtext\; id="EditorElement\_92346"></mtext><mn\; id="EditorElement\_92347">9</mn><mn\; id="EditorElement\_92348">0</mn><mi\; id="EditorElement\_92349">)</mi>$

printf$("$D$")$; $,$ printf$("$B$")$;

else else

printf$("$F$")$; $,$ printf$("$A$")$;